Stents are used for various reasons within the vasculature, such as flow diversion or restoring blood flow where there is stenosis. The following specification relates to stent designs that could be used for a variety of situations including treating bifurcation aneurysms at a branch vessel, stent designs to augment the radial strength of braided stents, stents with regions of differing porosity, and methods of attaching stents together.
All of the following applications are hereby incorporated by reference in their entireties: U.S. Provisional Patent Application Ser. No. 61/422,604 filed Dec. 13, 2010 entitled Stent; U.S. Provisional Patent Application Ser. No. 61/425,175 filed Dec. 20, 2010 entitled Polymer Stent And Method Of Manufacture; International Patent Application No. PCT/US2010/061627, International Filing Date 21 Dec. 2010, entitled Stent; U.S. Provisional Patent Application Ser. No. 61/427,773 filed Dec. 28, 2010 entitled Polymer Stent And Method Of Manufacture 2; and U.S. Nonprovisional patent application Ser. No. 13/003,277 filed Jan. 7, 2011 entitled Stent.
The present invention relates to devices for the treatment of body cavities, such as the embolization of vascular aneurysms and the like, and methods for making and using such devices.
The occlusion of body cavities, blood vessels, and other lumina by embolization is desired in a number of clinical situations. For example, the occlusion of fallopian tubes for the purposes of sterilization, and the occlusive repair of cardiac defects, such as a patent foramen ovale, patent ductus arteriosis, and left atrial appendage, and atrial septal defects. The function of an occlusion device in such situations is to substantially block or inhibit the flow of bodily fluids into or through the cavity, lumen, vessel, space, or defect for the therapeutic benefit of the patient.
The embolization of blood vessels is also desired to repair a number of vascular abnormalities. For example, vascular embolization has been used to control vascular bleeding, to occlude the blood supply to tumors, and to occlude vascular aneurysms, particularly intracranial aneurysms.
In recent years, vascular embolization for the treatment of aneurysms has received much attention. Several different treatment modalities have been shown in the prior art. One approach that has shown promise is the use of thrombogenic microcoils. These microcoils may be made of biocompatible metal alloy(s) (typically a radio-opaque material such as platinum or tungsten) or a suitable polymer. Examples of microcoils are disclosed in the following patents: U.S. Pat. No. 4,994,069—Ritchart et al.; U.S. Pat. No. 5,133,731—Butler et al.; U.S. Pat. No. 5,226,911—Chee et al.; U.S. Pat. No. 5,312,415—Palermo; U.S. Pat. No. 5,382,259—Phelps et al.; U.S. Pat. No. 5,382,260—Dormandy, Jr. et al.; U.S. Pat. No. 5,476,472—Dormandy, Jr. et al.; U.S. Pat. No. 5,578,074—Mirigian; U.S. Pat. No. 5,582,619—Ken; U.S. Pat. No. 5,624,461—Mariant; U.S. Pat. No. 5,645,558—Horton; U.S. Pat. No. 5,658,308—Snyder; and U.S. Pat. No. 5,718,711—Berenstein et al.; all of which are hereby incorporated by reference.
Stents have also been recently used to treat aneurysms. For example, as seen in U.S. Pat. No. 5,951,599—McCrory and U.S. Pub. No. 2002/0169473—Sepetka et al., the contents of which are incorporated by reference, a stent can be used to reinforce the vessel wall around the aneurysm while microcoils or other embolic material are advanced into the aneurysm. In another example seen in U.S. Pub. No. 2006/0206201—Garcia et al. and also incorporated by reference, a densely woven stent is placed over the mouth of the aneurysm which reduces blood flow through the aneurysm's interior and ultimately results in thrombosis.
In addition to flow diversion and occlusion, the present invention can also be used in applications where high coverage or low porosity is desirable. For example, when treating carotid artery stenosis with a stent, emboli or particulates may be dislodged during stent deployment or post-deployment dilatation. Since these emboli can become lodged in the brain and cause a stroke, it is desirable to provide a stent with low porosity to entrap the particulates. Another application of a high coverage stent is in areas of the body prone to thrombus formation such as in coronary bypass grafts (also called saphenous vein grafts or SVG) and arteries and veins in the lower extremities. Since the thrombus can dislodge and occlude downstream tissues, it is desirable to deploy a high coverage device of the instant invention to cover and/or entrap the thrombus to prevent it from migrating.